In one incident, former WWE wrestler Shawn Daivari, chokes out a drunken rider who was threatening passengers on the L.A. line. Fox 9 News aired this account:

In another incident, this time in Phoenix, a 3-on-1 fight in a train is broken up by a samurai sword welding bystander. Here's the video from ABC 15:

Clearly, incidents like these are best viewed from the safety of a computer screen. And, thankfully, serious incidents don't appear to be an issue on Hampton Roads Transit's light rail or bus lines.

HRT spokesman Tom Holden said he wasn't aware of any local incidents that came anywhere near the level of intensity displayed in the videos. Most incidents, he said, are minor in nature and involve things like fare evaders or "homeless guys wandering about."